1. Field of the Invention
This invention relates generally to a motor vehicle powertrain and, in particular, to use of the powertrain as a power source for equipment that is onboard or extrinsic to the vehicle.
2. Description of the Prior Art
The engine of a motor vehicle can be used to supply power through a power take-off (PTO) to onboard equipment, such as a hydraulic pump that provides pressure to support and move a snowplow blade or a bucket boom, and to extrinsic equipment, such as a water pump or electric generator at a construction site, ranch or farm.
A conventional PTO is driven downstream of a torque converter turbine, which is hydrokinetically coupled to the engine shaft through an impeller, driveably coupled to the engine. A conventional PTO unit transmits no power when the vehicle is stopped, though the selected position of the transmission gear selector is either the reverse-range or drive-range because. For a conventional PTO to provide power to a user, the transmission must transmit power to its output
In heavy truck applications, a PTO assembly generally is located axially between a transmission bell housing and the gearbox. But this arrangement does not package well in light trucks. It requires changing the rear position of the transmission, which causes mount/cross and drive shaft complexities, and is incompatible with high volume manufacturing.
A need exists in the light truck industry for a live PTO that is driven directly by the engine output regardless of the operating state of the transmission, and permits a one-piece transmission case and common driveshafts whether the vehicle is equipped with an optional PTO or the PTO is not incorporated in the vehicle.